许愿墙

  <!DOCTYPE html>
  <html lang="en">
   
  <head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <meta http-equiv="X-UA-Compatible" content="ie=edge">
  <title>许愿墙</title>
  <style>
  * {
  margin: 0;
  padding: 0;
  }
   
  html {
  height: 100%;
  background: linear-gradient(0deg, rgb(171, 212, 238), deepskyblue);
  }
   
  body {
  position: relative;
  }
   
  .container {
  100%;
  height: 630px;
  position: relative;
  }
   
  input[id="res"] {
  300px;
  height: 40px;
  position: fixed;
  bottom: 30px;
  left: 50%;
  margin-left: -150px;
  padding-left: 15px;
  border: 1px solid #ccc;
  outline: none;
  border-radius: 5px;
  }
   
  .item {
  150px;
  height: 150px;
  position: absolute;
  top: 100px;
  left: 100px;
  box-shadow: 0 2px 10px 1px rgba(0, 0, 0, 0.2);
  padding: 10px;
  border-radius: 15px/5px 10px 10px 0;
  transform: skew(-1deg);
  cursor: move;
  }
   
  .item span {
  position: absolute;
  right: 6px;
  bottom: 4px;
  font-size: 12px;
  color: #eee;
  cursor: pointer;
  }
   
  .comfirmBtn {
  100px;
  height: 40px;
  position: fixed;
  bottom: 31px;
  left: 64%;
  border: none;
  outline: none;
  border:1px solid;
  border-radius: 10px;
  cursor: pointer;
  }
  </style>
  </head>
   
  <body>
  <div class="container"></div>
  <input type="text" name="res" id="res" placeholder="随便说说吧...点击确认按钮发布">
  <button class="comfirmBtn">点击发布</button>
  <script>
  // 获取DOM元素
  let container = document.getElementsByClassName('container')[0];
  let btn = document.getElementsByClassName('comfirmBtn')[0];
  // 默认的许愿单文字
  let wishes = ['新年来好运', '能找一份好工作', '日语等级考试通过', '能交上女朋友', '新年来好运', '能找一份好工作', '日语等级考试通过', '能交上女朋友'];
  // 许愿单随机背景颜色
  let bgcColors = ['#96c2f1', '#bbe1f1', '#e3e197', '#f8b3d0', '#ffcc00', 'rgba(255,123,123,1)', 'yellowgreen', 'pink', 'skyblue'];
  // 渲染函数 新增一个div元素 做好css配置以后将该div返回
  let render = function (wish) {
  // 生成随机数据
  let bgcColorIndex = Math.floor(Math.random() * bgcColors.length);
  let randomTop = Math.floor(Math.random() * (630 - 150)); // container容器的高减去150
  let randomLeft = Math.floor(Math.random() * (window.innerWidth - 175)); // left值在减去盒子宽度150的基础上多减去了25px
  let content = `<div class="item" >${wish}<span>关闭</span></div>`;
  container.innerHTML += content;
  }
  // 页面刚开始加载时 将默认的许愿单加载到页面上
  window.onload = function () {
  // 遍历所有默认的许愿单 将其渲染到页面上面
  for (let i = 0; i < wishes.length; i++) {
  render(wishes[i]);
  }
  }
  // 发布新内容函数
  let newContent = function () {
  if (res.value !== '') {
  let inputText = res.value;
  render(inputText);
  res.value = '';
  } else {
  alert('不能为空!');
  }
  }
  // 有两种方式可以添加新的愿望 按回车键 或者 点击发布按钮
  document.onkeyup = function (e) {
  if (e.keyCode === 13) {
  newContent();
  }
  }
  // 为确认按钮添加点击事件
  btn.onclick = newContent;
   
  // 通过事件委托 给整个document绑定点击事件 但是只有点击span元素的时候 移除其父节点
  document.onclick = function (e) {
  if (e.target.nodeName === 'SPAN') {
  container.removeChild(e.target.parentNode);
  }
  }
   
  // 设置许愿单拖动
  container.onmousedown = function (e) {
  if (e.target.className === 'item') {
  let offsetX = parseInt(e.target.style.left); // 获取当前的x轴距离
  let offsetY = parseInt(e.target.style.top); // 获取当前的y轴距离
  let innerX = event.clientX - offsetX; // 获取鼠标在方块内的x轴距
  let innerY = event.clientY - offsetY; // 获取鼠标在方块内的y轴距
  let that = e.target;
  document.onmousemove = function (e) {
  that.style.left = event.clientX - innerX + "px";
  that.style.top = event.clientY - innerY + "px";
  // 边界判断
  if (parseInt(that.style.left) <= 0) // 左边边界
  {
  that.style.left = "0px";
  }
  if (parseInt(that.style.top) <= 0) // 上边边界
  {
  that.style.top = "0px";
  }
  if (parseInt(that.style.left) >= window.innerWidth - 175) // 右边边界 = 窗口宽度 - 盒子大小 稍微多减去了25px
  {
  that.style.left = window.innerWidth - 175 + "px";
  }
  if (parseInt(that.style.top) >= 480) // 下边边界 = 630 - 150
  {
  that.style.top = 480 + "px";
  }
  }
   
  document.onmouseup = function () {
  document.onmousemove = null;
  document.onmouseup = null;
  }
   
   
  }
   
   
   
  }
  </script>
  </body>
   
  </html>
原文地址:https://www.cnblogs.com/qilin0/p/11444421.html